The present invention relates to a shield for a needle and more particularly to a safety shield assembly that may be used in conjunction with a syringe assembly, a hypodermic needle, a needle assembly, a needle assembly with a needle holder, a blood collection needle, a blood collection set, an intravenous infusion set or other fluid handing devices or assemblies that contain piercing elements.
Disposable medical devices having piercing elements for administering a medication or withdrawing a fluid, such as hypodermic needles, blood collecting needles, fluid handling needles and assemblies thereof, require safe and convenient handling. The piercing elements include, for example, pointed needle cannula or blunt ended cannula.
Safe and convenient handling of disposable medical devices is recognized by those in the medical arts so as to minimize exposure to blood borne pathogens. Safe and convenient handling of disposable medical devices results in the disposal of the medical devices intact.
As a result of this recognition, numerous devices have been developed for shielding needles after use. Many of these devices are somewhat complex and costly. In addition, many of these devices are cumbersome to use in performing procedures. Furthermore, some of the devices are so specific that they preclude use of the device in certain procedures or with certain devices and/or assemblies. For example, some devices employ very short thin needle cannulas. A shield designed to lock near the distal end of one needle cannula might not engage a much shorter needle cannula. Additionally, a shield designed to lock with a wider gauge needle cannula might be more likely to generate a spray upon engaging a much narrower needle cannula. Furthermore, it may be desirable to reduce the force required to effect shielding without reducing the audible and tactile indications of complete shielding.
Therefore, there exists a need for a safety shield assembly: (i) that is manufactured easily; (ii) that is applicable to many devices; (iii) that is simple to use with one hand; (iv) that can be disposed of safely; (v) that does not interfere with normal practices of needle use; (vi) that has tactile features whereby the user may be deterred from contacting the needle, the user may easily orient the needle with the patient and easily actuate and engage the shield assembly; (vii) that has visual features whereby the user may be deterred from contacting the needle, the user may easily orient the needle with the patient and easily actuate and engage the shield assembly; (viii) that is not bulky; (ix) that includes means for minimizing exposure to the user of residual fluid leaking from the needle; and (x) provides minimal exposure to the user because the needle shield is immediately initiated by the user after the needle is withdrawn from the patient""s vein.
The present invention is a safety shield assembly that comprises: a shield; means for connecting the shield to a fluid handling device that contains a piercing element, such as needle; means for pivoting the shield away from the needle; and means for securely covering and/or containing the needle within the shield.
Preferably, the shield comprises a rearward end, a forward end, a slot or longitudinal opening for housing the used needle in the forward end, means for securing the needle in the slot, means for guiding the needle into the slot, means for connecting the shield and the fluid handling device, means for guiding the user""s fingers to move the shield into various positions, and means for retaining the shield securely over the used needle.
Desirably, the means for connecting the shield to the fluid handling device is a collar. Preferably, the shield is connected movably to a collar which is connected to a fluid handling device.
Preferably, the shield is connected to the collar by a hanger bar that engages with a hook arm on the collar so that the shield may be pivoted with respect to the collar into several positions. It is within the purview of the present invention to include any structure for connecting the shield to the collar so that the shield may be pivoted with respect to the collar. These structures include known mechanical hinges and various linkages, living hinges, or combinations of hinges and linkages.
Most preferably, the shield is connected to the collar by an interference fit between the hanger bar and the hook bar. Therefore, the shield always is oriented in a stable position and will not move forward or backwards unless movement of the shield relative to the hanger bar and the hook bar is initiated by the user.
Alternatively, the collar and at least a portion of the shield may be a unitary one-piece structure. The one-piece structure may be obtained by many methods, including molding the shield and the collar as a one-piece unit, thereby eliminating the separate shield and collar during the manufacturing or assembly process.
The assembly of the present invention may further comprise tactile and visual means for deterring the user from contacting the needle, providing easy orientation of the needle with the patient and providing the user with a guide for actuation and engagement with the shield.
The assembly of the present invention may further comprise means for minimizing exposure by the user to residual fluid leaking from a used needle. For example, a polymer material, such as a gel, may be located in the shield.
Most desirably, the assembly of the present invention is such that the cooperating parts of the assembly provide the means for the shield to move into a forward position over the needle. Thus, by simple movement of the shield into a forward position over the used needle, the assembly is ready for subsequent disposal. Therefore, the safety shield assembly of the present invention provides minimal exposure of the user to a needle because the shielding is initiated by the user immediately after the needle is withdrawn from the patient""s vein.
Desirably, the assembly of the present invention may be used with a syringe assembly, a hypodermic needle, a needle assembly, a needle assembly with a needle holder, a blood collection set, an intravenous infusion set or other fluid handling devices. Preferably, the assembly of the present invention is used with a needle assembly comprising a needle and a hub. Preferably the needle is a conventional double ended needle.
Most preferably, the present invention is used with a needle assembly comprising a hub and a needle connected to the hub whereby the needle comprises a non-patient end and an intravenous end. The collar of the present invention may comprise a hook arm and the shield may be connected movably to the hook arm. Thus the shield may be pivoted with respect to the collar and moved easily into several positions.
Preferably, the collar is fitted non-rotatably with the hub of the needle assembly. Additionally, the collar includes cooperating means that mate with reciprocal means on the shield to provide a clear audible and tactile indication of shielding. The cooperating means on the collar may include generally chevron-shaped projection formed on a side of the collar substantially diametrically opposite the hook arm or other such structure that provides the hinge connection to the shield. The chevron-shaped structure includes a forward or distal point. Slanting surfaces diverge and extend proximally from the distal point. The slanting surfaces cooperate with the reciprocal means on the shield to generate a deflection of the sidewalls of the shield away from one another. The chevron-shaped structure further includes proximal ends that are convexly arcuate. The convexly arcuate ends of the chevron-shaped structure on the collar cooperate with the reciprocal means on the shield and with the resiliently deflectable sidewalls of the shield to generate the tactile and audible indication of shielding.
The shield preferably includes a proximal or rearward portion that is hingedly connected to the collar and a distal or forward portion that comprises a support extending unitarily from the rearward portion of the shield. The shield may further comprise a cannula channel securely mounted to at least the support of the forward portion. The channel may comprise a top wall securely connected to the support of the shield and a pair of opposed spaced apart sidewalls extending downwardly from the top wall. The spacing between the sidewalls is selected to accommodate the needle cannula in the channel. At least one of the sidewalls of the cannula channel is formed with at least one cannula finger lock that projects angularly toward the top wall of the cannula channel. The cannula finger lock is dimensioned, disposed and aligned to contact the needle cannula when the shield approaches the second position. Contact between the needle cannula and the cannula finger lock will cause the cannula finger lock to resiliently deflect toward the sidewall from which the cannula finger lock extends. Sufficient rotation of the shield will cause the needle cannula to pass the cannula finger lock. As a result, the cannula finger lock will resiliently return to or toward its undeflected condition for securely trapping the needle cannula in the shield.
The top wall of the cannula channel may comprise means for engaging reciprocal means on the support of the forward portion of the shield. The mounting means on the cannula channel may be disposed in a non-central position relative to the longitudinal direction of the channel. Thus, the cannula channel can be mounted to the shield support in either of two alternate orientations that are rotated 180xc2x0 from one another. In a first rotational orientation, the cannula channel projects distally or forwardly beyond the support of the shield. In a second rotational orientation, the cannula channel projects rearwadly or proximally from the support of the shield to overlie the rearward portion of the shield. Thus, the first rotational orientation of the cannula channel ensures that the pointed distal end of a long needle cannula is surrounded by the cannula channel and engaged by the cannula finger locks. The second rotational orientation of the cannula channel ensures that a shorter needle cannula is surrounded by the cannula channel and engaged by the cannula finger locks.
The cannula channel may have a proximal or rear end configured for engaging the collar or hub when the shield is in its second position. Engagement of the channel with the collar or hub may contribute to locked retention of the shield in the second position. Additionally, engagement of the proximal end of the cannula channel with the collar or hub may further support the channel and prevent excessive deformation of the channel.
Preferably, the collar is fitted with the hub of the needle assembly so that the collar cannot rotate around the hub. Alternatively, the collar and hub may be a unitary one-piece structure. The one piece structure may be accomplished by many methods including molding the collar and the hub as a one-piece unit thereby eliminating the need to separately assemble the collar to the hub during the manufacturing process.
Most preferably, the collar is fitted with the hub of the needle assembly so that the bevel surface or bevel up surface of the intravenous or distal end of the needle faces the same side of the collar when the shield is in the first position. Alignment of the collar, hub, shield and needle with the bevel surface up makes it easier to insert the needle into the patient without manipulating the assembly. The orientation of the intravenous end of the needle with the bevel up assures the user that the needle is properly oriented for use and does not require any manipulation before use. Most notably, the orientation of the shield provides a visual indication to the user of the orientation of the bevel surface of the needle.
Preferably, the shield is capable of pivoting from a first position where the intravenous end of the needle is exposed and bevel up, to an intermediate position where the needle is partially covered, to a second position where the needle is covered completely.
Alternatively, it is within the purview of the present invention that the collar, hub and at least a portion of the shield may be a unitary one-piece structure. The one-piece structure may be accomplished by many methods including molding the shield, collar and hub as a one-piece unit thereby eliminating the need to separately assemble the shield, collar and hub during the manufacturing process.
It is an advantage of the present invention that the shield covering the used intravenous end of the needle provides easy containment of the used needle. A further advantage of the shield is that it will only move upon initiation by the user.
The assembly of the present invention when used with a fluid handling device is also easily disposable when removed from a conventional needle holder, or other such device.
A notable attribute of the present invention is that it is easily adaptable with many devices. For example, the invention is usable with syringe assemblies, hypodermic needles, needle holders, blood collection needles, blood collection sets, intravenous infusion sets such as catheters or other fluid handling devices or assemblies that contain piercing elements.
Another notable attribute of the present invention is that the tactile and visual features deter the user from touching the needle, allow the user to easily orient the needle with the patient and guide the user to actuate and engage the shield of the assembly.